Approach to Ultrasound of the Wrist Disclosure I have no commercial or financial interests related to the subject matter of this presentation Linda robyn, MD, FRCC MSK Radiologist Objectives At the end of this presentation, the participant will be able to: 1. Understand anatomy of the wrist flexor/extensor compartments 2. Have an approach to ultrasound examination of the wrist 3. Understand common uses and pathologies seen on wrist ultrasound Outline Imaging technique Normal Anatomy Common athologies: Tendons: Tendinosis, Dequervain s Disease, tear Joints: Arthritis (Inflammatory, Depositional, OA) Nerves: Neuropathy (Ulnar n, Median n, Radial n) Other: ganglion cyst, intersection syndrome, implantation dermoid, foreign body Technique Technique osition opposite patient with table 1
Technique Elevate on small towel Control probe with finger on patient Technique 10-17 MHz linear array transducer Small foot print transducer (hockey stick) Stand off pad or gel Anatomy Anatomy Extensor Compartment 6 Extensor compartments Extensor carpi radialis brevis ECRB Extensor carpi radialis longus ECRL Extensor pollicis brevis EB Abductor pollicis longus AL 1 Extensor pollicis longus EL 2 Extensor digitorum ED Extensor indicis EI Extensor digiti minimi EDM Extensor carpi ulnaris ECU 3 4 5 Lister s tubercle Radius Ulna 6 Anatomy Extensor Compartment Anatomy Extensor Compartment Compartment 3 crosses over 2 1 2 3 4 5 Lister s tubercle Radius Ulna 6 2
Anatomy Flexor Compartment Anatomy Flexor Compartment almaris Longus Retinaculum Median nerve Flexor Carpi Radialis Flexor ollicis Longus S Flexor digitorum superficialis FDS S Flexor digitorum profundus FD Anatomy Flexor Compartment Retinaculum Anatomy Guyon s Canal S Median nerve S Anatomy Guyon s Canal Structure Semi-rigid canal Medial pisiform, FCU Superficial palmar carpal ligament Deep flexor retinaculum assage of ulnar artery and nerve FCU FCU Tendons Echogenic and fibrillar Uniform thickness Synovial sheath thin echogenic line around tendon Small amount of fluid normal 3
Structure Structure Ligaments Echogenic and fibrillar Nerves Multiple axons bundled together in fasicles Grouped together by loose connective tissue epineurium Multiple parallel hypoechoic fasicles Surrounded by echogenic perineurium itfalls itfalls Retinaculum Normal structures Extensor retinaculum Muscle Appears hypoechoic Not fluid itfalls Transducer itfalls Anisotropy Beam reflected away from transducer if probe not perpendicular to the structure Appears hypoechoic Transducer Reflector appears bright Solution: Heel toe transducer in longitudinal Rock transducer in transverse Reflector appears dark 4
Tenosynovitis Common athologies Distention of tendon sheath with fluid or synovial hypertrophy ossible hyperemia Tendinosis Hypoechoic tendon enlargement Variable hyperemia De Quervain s Disease Repetitive thumb movements ain over radial styloid ositive Finkelstein test Cmpt 1 tendons AL EB Extensor retinaculum www.clinicalexams.co.uk www.quizlet.com De Quervain s Disease Thickening of extensor retinaculum Hypoechoic, thickened tendon Tenosynovitis hyperemia Tendon Tear artial thickness tear Incomplete anechoic cleft Full thickness tear Complete discontinuity with retraction of tendon ends Dynamic assessment improves accuracy itfall: Some tendons can have multiple tendon slips (AL) 5
Tendon Tear EL Tear Common to occur at Lister s tubercle Tendon Tear EDM Tear Arthritis - Inflammatory Hallmark is synovial hypertrophy Usually hypoechoic Synovitis when hyperemia on power or color Doppler Arthritis - Inflammatory Erosions Can see at various joints Look for early changes at ulnar styloid Ulna Arthritis - Depositional Crystals deposit around joints, ligaments, tendons Gout, CD, HADD HADD calcific periarthritis Monoarticular May have antecedent trauma ainful simulate infection F periarticular calcifications Arthritis - Depositional HADD calcific periarthritis Echogenic calcium deposits at joint margin Hypoechoic synovial thickening Hyperemia 6
Arthritis - Depositional CD Echogenic calcium deposits at joint margin Hypoechoic synovial thickening Hyperemia Arthritis - OA Common location at wrist 1 st CMC and STT Osteophytes +/- effusion/synovitis F correlation Neuropathy Ulnar Nerve Neuropathy Ulnar Nerve Ulnar Tunnel Syndrome Guyon s Canal Symptoms depend on location of compression/injury 3 zones Numbness & pain 5 th finger and ulnar ½ of 4 th finger Weakness intrinsic muscles www.orthobullets.com Ulnar Tunnel Syndrome Guyon s Canal Causes: Compression of ulnar n. Cyclists (handlebar palsy) Trauma - hook of hamate # Inflammatory arthritis Ganglion cyst www.capefearcyclists.org www.emedmd.com Neuropathy Ulnar Nerve Guyon s canal Carpal Tunnel Syndrome Numbness & ain median n. distribution First 3 ½ digits Trauma, repetitive use, arthritis, pregnancy, SOL www.emedmd.com 7
Carpal Tunnel Syndrome Hypoechoic enlarged nerve at and prox to retinaculum Measure at level of pisiform & Flexor retinaculum Measurements variable: <8 mm 2 normal 8 12 mm 2 borderline >12 mm 2 abnormal Compare area proximal and distally where enlarged: Enlargement 2mm 2 (90% sensitivity and 100% specificity) Carpal Tunnel Syndrome Hypoechoic enlarged nerve at and prox to retinaculum Carpal Tunnel Syndrome Low lying MT junction with muscle belly in carpal tunnel Carpal Tunnel Syndrome Fibrolipomatous Hamartoma of Median n. Screw Impingement Metalwork can impinge upon nerves and tendons Dynamic assessment helpful 8
Neuropathy Radial Nerve Superficial branch innervates dorsum of hand Neuropathy Radial Nerve Can be impinged by: Ganglion cyst De Quervain s tenosynovitis (Wartenberg s Syndrome) Eorthopod.com Ganglion Cysts Arise from joints or tendons Thin connective tissue capsule, no synovial lining Gelatinous fluid Rx: aspiration and/or steroid injection Can recur Intersection Syndrome Overuse tenosynovitis Occurs around the intersection of the 1 st (AL, EB) and 2 nd (ECRL, ECRB) cmpts within forearm Weightlifters, rowers, racket sport players Eorthopod.com Iop.net.au Intersection Syndrome Iop.net.au Distal Intersection Syndrome Tenosynovitis of the 3 rd (EL) and 2 nd compartments Distal to Lister s tubercle Tendon sheaths connected by foramen Inflammation of one compartment spreads to other Iop.net.au 9
Distal Intersection Syndrome Iop.net.au Implantation Dermoid Hx previous puncture Implantation of epidermal fragments into dermis Grows and forms cyst lined with squamous epithelium Small, painless nodule Hypoechoic No hyperemia Foreign Bodies History may or may not provided Can cause swelling, redness, hematoma, hyperemia Foreign Bodies F for radiopaque FB Summary Reviewed anatomy of the wrist including flexor/extensor compartments Described an approach to ultrasound examination of the wrist Reviewed common uses and pathologies for wrist ultrasound The End Linda robyn, MD FRCC linda.probyn@sunnybrook.ca 10
References Chiavaras MM, Jacobson JA, Yablon CM, Kalume Brigido M, Girish G. itfalls in Wrist and Hand Ultrasound. AJR:203, September 2014 Lee JC, Healy JC. Normal Sonographic Anatomy of the Wrist and Hand. Radiographics 2005; 25:1577-1590 Jacobson JA, Girish G, Jiang Y, Sabb B. Radiographic Evaluation of Arthritis: Degenerative joint Disease and Variations. Radiology 2008;248(3):737-747 Jacobson JA, Girish G, Jiang Y, Resnick D. Radiographic evaluation of arthritis: inflammatory conditions. Radiology 2008;248(2):378-389 Rousset, Vuillemin-Bodaghi V, Laredo J, arlier-cuau C. Anatomic Variations in the First Extensor Compartment of the Wrist: Accuracy of US. Radiology 2010;257(2):427-433 Klauser AS, Halpern EJ, De Zordo T, et al. Carpal tunnel syndrome assessment with US: value of additional cross-sectional area measurements of the median nerve in patients versus healthy volunteers. Radiology 2009; 250:171-177 11